Soybean varieties have a genetic yield potential greater than 100 bu per acre. However this yield potential is never reached under field conditions. Environmental conditions are usually never adequate to fully "unlock" the full genetic potential of a variety. The interaction between genetics and environment and how that translates into yield is largely unknown. Yet there are fundamental management decisions that give the best opportunity to maintain high yield. Understanding how a soybean plant develops through the season will provide insight into selection of management decisions that should lead to maintaining the yield potential. After variety selection, planting date is the most important management decision a grower has to make every year.